Far-uvc germicidal system

Abstract

A germicidal lighting system uses far-UVC lamps emitting frequencies that do not harm humans, for example 222 nm. The presence of a person is detected using sensors, and the far-UVC lamps are turned on when a person is present and off when no one is present. This may be applied to a person's whole body or, for example, a hand or hands. A far-UVC optical system for a germicidal lighting system may include a wavelength selective mirror arranged to receive far-UVC light from a far-UVC light source and to disproportionately reflect the far-UVC light in at least one wavelength of the far-UVC light relative to at least another wavelength of light emitted by the far-UVC light source. A far-UVC light source may be placed in a reflective enclosure to direct light through an opening. The reflective enclosure or a mirror to which the light is directed may be rotated.

1 . A far-UVC optical system for a germicidal lighting system, the far-UVC optical system comprising:
 a far-UVC light source; and   a wavelength selective mirror arranged to receive far-UVC light from the far-UVC light source and to disproportionately reflect the far-UVC light in at least one wavelength of the far-UVC light relative to at least another wavelength of light emitted by the far-UVC light source.   
     
     
         2 . The far-UVC optical system of  claim 1  in which the wavelength selective mirror comprises a wavelength selective coating over a base surface of the wavelength selective mirror. 
     
     
         3 . The far-UVC optical system of  claim 2  in which the wavelength selective coating comprises a chemical that absorbs the at least another wavelength and does not substantially absorb the at least one wavelength. 
     
     
         4 - 17 . (canceled) 
     
     
         18 . A germicidal lighting system for disinfecting skin or clothing of a human, the germicidal lighting system comprising:
 a structure defining an opening for accommodating the human or a body part of the human;   one or more sensors arranged on the structure to generate sensor information indicative of the presence of the human or body part within the opening;   one or more far-UVC lamps arranged on the structure to emit far-UVC light to disinfect the human or human body part when the human or human body part is positioned within the opening, and   a processor connected to the sensors and to the far-UVC lamps and configured to analyze the sensor information to determine that the human or body part is present within the opening, and to activate the far-UVC lamps based on the determination that the human or body part is present within the opening.   
     
     
         19 . The germicidal lighting system of  claim 18  in which light emitted by the one or more far-UVC lamps has a wavelength within the range of 207 to 222 nm. 
     
     
         20 - 21 . (canceled) 
     
     
         22 . The germicidal lighting system of  claim 18  in which the opening is a receptacle arranged to receive a hand or hands. 
     
     
         23 . The germicidal lighting system of  claim 22  in which the hand or hands are two hands, and the processor is configured to activate the one or more far-UVC lamps based on the determination that both hands are present simultaneously. 
     
     
         24 . The germicidal lighting system of  claim 22  further comprising a signal generation system, and in which the processor is configured to cause the signal generation system to generate a finishing signal based on the far-UVC light having been active for an amount of time sufficient to disinfect the hand or hands. 
     
     
         25 . The germicidal lighting system of  claim 24  in which the processor is configured to determine from the sensor information whether the hand or hands are remaining in the opening, and to cause the signal generation system to send the finishing signal based on the hand or hands having been within the opening for the amount of time. 
     
     
         26 - 38 . (canceled) 
     
     
         39 . A far-UVC optical system for a germicidal lighting system, the far-UVC optical system comprising:
 a far-UVC light source; and   a reflective enclosure around the far-UVC light source, the reflective enclosure having an opening and having reflective walls arranged to direct far-UVC light from the far-UVC light source to the opening.   
     
     
         40 . The far-UVC optical system of  claim 39  in which the reflective walls comprise at least one concave portion. 
     
     
         41 . The far-UVC optical system of  claim 39  in which the opening is not in direct line of sight from at least a center of the far-UVC light source. 
     
     
         42 . The far-UVC optical system of  claim 39  in which the reflective walls are arranged as a spiral. 
     
     
         43 . The far-UVC optical system of  claim 40  in which the reflective walls include concave portions arranged around a direct line of sight from the far-UVC lamp to an intermediate position in the optical system to reflect generally to the intermediate position light emitted from the far-UVC lamp in directions other than the direct line of sight from the far-UVC lamp to the intermediate position. 
     
     
         44 . The far-UVC optical system of  claim 43  in which the far-UVC light source is a linear light source, the concave portions shaped in cross section to form portions of one or more ovals in a plane perpendicular to the light source. 
     
     
         45 . (canceled) 
     
     
         46 . The far-UVC optical system of  claim 43  in which the reflective walls also include an end mirror at the intermediate position in the optical system, the end mirror arranged to direct to the opening the far-UVC light from the concave portions of the reflective walls and from the direct line of sight from the far-UVC lamp. 
     
     
         47 . The far-UVC optical system of  claim 46  further comprising a second end mirror in a second direct line of sight from the far-UVC lamp and arranged to direct the far-UVC light through a second opening, the second end mirror located at a second intermediate position of the optical system and second concave portions being arranged around the second direct line of sight from the far-UVC lamp to guide generally to the second intermediate position light emitted from the far-UVC lamp in directions other than the second direct line of sight from the far-UVC lamp to the second intermediate position. 
     
     
         48 . The far-UVC optical system of  claim 47  in which the second end mirror is arranged opposite to the end mirror. 
     
     
         49 . The far-UVC optical system of  claim 39  in which the reflective walls comprise a wavelength selective mirror arranged to receive the far-UVC light from the far-UVC light source and to disproportionately reflect the far-UVC light in at least one wavelength of the far-UVC light relative to at least another wavelength of light emitted by the far-UVC light source. 
     
     
         50 - 56 . (canceled) 
     
     
         57 . The far-UVC optical system of  claim 39  further comprising an additional mirror arranged to receive the far-UVC light after it exits the opening. 
     
     
         58 - 72 . (canceled)